There are many types of article for which it is desirable to provide a visual indication that it has been breached, which may in some circumstances be indicative of accidental damage to the article, and in other circumstances indicative of tampering with the article.
An example of an article for which it is desired to provide a visual indication of accidental damage is a protective glove. Protective gloves are worn by surgeons in the course of surgical operations and are increasingly worn by other medical personnel (such as nurses, dentists and ambulance operatives), as well as other emergency workers, in view of concern over cross-infection in connection with diseases such as hepatitis B and acquired immune deficiency syndrome (AIDS).
The basic rationale behind the use of such gloves is that they should provide a complete barrier between the medical or emergency worker and the patient. Unfortunately, there is a risk of damage to the gloves by the use of sharp instruments such as scalpels, needles and the like; such damage is not always immediately detectable.
Examples of articles where it is desired to provide a visual indication of accidental damage or tampering include containers (particularly containers which are intended to provide security for the contents), coin-meters, seals on lorries and other vehicles, and the like. For such products it is often desirable to provide a visual indication of when a seal has been broken.
It is an object of the invention to provide tamper- or damage-indicating members, and methods for detecting breach (either accidental or as a result of unauthorised tampering) of such members.